On February 11, EPA-OTAQ posted two revised SIP and conformity guidance documents for quantifying and using emissions reductions from diesel retrofits and commuter programs. You can find the documents at the following link.
http://www.epa.gov/otaq/stateresources/transconf/policy.htm#quantify
- Diesel Retrofits: Quantifying and Using Their Emission Benefits in SIPs and Conformity – Guidance for State and Local Air and Transportation Agencies (PDF) (70 pp, 1.0MB, EPA-420-B-14-007, February 2014) (supersedes EPA420-B-06-005, June 2006)
- Commuter Programs: Quantifying and Using Their Emission Benefits in SIPs and Conformity (PDF) (13 pp, 498K, EPA-420-B-14-004, February 2014) (supersedes EPA-420-B-07-015, October 2007)